In civilized countries tables have come to be used on a very wide scale so that their design, function and different possible uses are quite well known. They are generally used as supports or rests for many different things and purposes and as a rule are made of such a height that a person in an upright or seated position may quickly and simply take up and put down the things on the table. The general design of a table is such that there is a table top and at least three or, as is most frequently the case, four table legs. There is a very wide range of different possible table sizes, the selection of the table size being dependent on the amount of free space in which the table may be put. For manufacturing a table, in the simplest case the first step is making a selection of the right size of table top and then fixing the legs thereto. But for some less common and somewhat complex designs of table, which make possible for the table top size to be changed after the table design has been completed, the size of the table top is fixed once and for all when the different parts of a table are put together. However in the general run of things, it is a shortcoming that before the size of a table top may be changed in a factory producing tables, a more or less complex process of retooling of the production machines is needed, this being more specially the case if extruding or injection molding machines are being used.